Single-phase gas or vapor electric apparatus.



PL. H. THOMAS. SINGLE PHASE GAS 0R VAPOR ELECTRIC APPARATUS.

AEPLICATION FILED-MAY 26. I9

I Patented. Dec. 14, 1915 IIVVE/l TOR rarnn rorrmn.

PERCY H. THOMAS OF MONTCLAIB, JERSEY, ASSIGNOR, BY MESNE ASSIGNMENTS, TOCOOPER HEWITT ELECTRIC COMP ANY, F HOBOKEN, NEW JERSEY, A CORPORA- TIONOF NEW EERSEY.

. smear-PHA E ens on vnron nnncrnrc arranarusl Specification ofLettersBatent.

Patented Dec. it, was.

Original application filed June 13, 1903, Serial No. 161,282. Dividedand this application filed may 26,

1911. Serial No. 629,632.

To allwkom it may concern:

Be it known that-I, PERCY H. THOMAS,

a citizen of the United States, and resident of Montclair, county ofEssex, State of New Jersey, have invented certain new and usefulImprovements in Single-Phase Gas or Vapor Electric Apparatus, of whichthe following is a specification. In an apparatus of the character shein certain patents to Peter Cooper Hewitt, for example Patents. 682,690to 682,699 inclusive, dated September 17th,. 1901', which is operated ondirect current circuits, it has been customary in starting to apply tothe terminals of the apparatus a momentary current of higher potentialthan that upon which the apparatus is designed to be op-. erated. Inemployingalternating currents,

it is possible to apply to the starting band a. higher potential derivedfrom the supply circuit.

.When the described reluctance to starting has once been broken down,current" may continue to flow through the-apparatus provided the appliedelectro-motivedorce is sufiiciently high and also provided that thedirection of flow be maintained uniformly. When, however, currents ofvarying'value or of alternate direction are applied to the apparatus,the electrode reluctance is liable to be re-formed shouldfthe currentvalue drop below a certain minimum, and is cer tain to be re-formedwhenthe direction of I flow is reversed. Thus in operating apparatus ofthis class by means of alternating currents or currentswhichvaryconsiderably value, provision has to be made for reinforcmg thelower values when .the current the purpose indicated by placing a chokea mand upon thesyste is of,unif orm direction and for repeatedlystarting the apparatus whenever the direction of the current changes. aU 'It has been proposed to provid'e-meansfor of suflicient capacity, theenergy stored on the rising current will be suflicient to maintaincurrent through the negative electrode until the supply circuit shallagain tend to increase the current flow in the. properdi- 1 variousorganizations have been proposed for preventmgthe negative alternationsfrom undoing the work of the positives.

For example, the amount of energy required from the choke-coil isconsiderably to such an organization, both the positive and negativealternations tend to pass through the lamp in the same direction.Meanwhile, the function of the chokecoilin delivering energy enough tosupply current for the. short period between alternations'is constantlycalled into play.

alternating current, the capacity of the choke coil might have to beconsiderable,

lessened if a path be provided for 'the me a-. Lt-IVG alternationsthrough the apparatus y means of a second positive electrode. With 170It might be supposed that in operating the vapor apparatus upon a singlephase ever, that an extra potential should be applied to enable thechoke coil in the first alternation afterstarting to absorb a sufiicientamount of energy so that 'it may discharge the ener y necessary tomaintain the lamp over the rst zero point, without fall:

ing below the minimum current.

It is the object of the present invention to-provide means for supplyingthis'extra initial potential, as" will presently appear, it beingunderstood that the additional volt,-

age thus withdrawn 'from the source willv generally be removed after'thestarting of I avoid the use of a supplemental elec Y trode by applyingtoone or both of the positive electrodes a supplementaryvelectro-motiveforce and trans erring the positive electrode or.electrodes to-the normal running point on the transformer winding afterstarting, without the interruption of the cir- 1 cuit. I

The high potential at the starting point the apparatus. This makes itpossible to 7 port-the current through the lamp; the

mayjbe obtained, if desired, through a. snap or quick break switch justas in a direct cur rent lamps In this case it issometimes necessary toclose and' open the switch a number of times in order to insure that themechanical break should occur at a favorable portion of high potentialimpulse.

I have illustrated my invention in the accompanying drawing, which showsthe application of my invention to a mercury vapor device having twoanodes, a cathode and utilizing an inductance'for control 'ng theoperation of the device. 5' e 15 1 is the container of a lamp of the character described above, the same containing, in this instance, anegative electrode, 5, of mercury and positive electrodes, 2 and 3,which ma be of iron. I

he device is fed from an auto trans-- former winding, 21, supplied fromtwo mains 13, 13. The cathode, 5, of the device is connected through an'inductance, 7, to an intermediate point, 8, of the winding 21. Otherportions of the windings 14-, 14, respe'ctively on the right and lefthand ends of the winding 21, have resistances 1-8, 18, connected inparallel with them, there being provided arms, 19, 19, adapted tocontact either with the windings 14 directly at two points oradapted tocontact with interm'ediate points on the resistances18, 18.

The conductors 13', 13 are assumed to be connected with a source ofsingle-phase alternating current. The operation of thev lamp is then asfollows: Assuming, for example, that the electrode 2 has a positivepotential with regard to the negative electlgode at the time of theapplication of the critical strain, current flowsfrom 2 to 5, .reachingfinally the proper value for the electro-motive-force. ,supplied and atthe sametime storing energy in 'the choke coil 7. During the latter partof the first alternation, as the voltageupon the positive electrode 2falls to zero, the energy previously stored in the choke coil 7continues the flow of current in 'the original direction. through thecoil until the potential upon the electrode 3 becomes positive in itsturn, whereupon electrode 3 will itself support the current through thelamp and, as its value rises in the second alternation, will increase Ithe current through the choke 'coil' 7 to the 5'5 maximum at the timeatwhich it is returning toward'zer'o. A's before-when the volt-. ageof"the'electrode 3 becomes too small to sup ort the 'current throughthechoke coil, 7, t iscoil sup lies energy-keeping the current flowing, ton hata decreaslng intensity, until electro e- 2'afterfhaving hadanegative value during' the-second alternation figa'in becemes positivein the third alternatlon, when-it is utilized to again sup-.

choke coil 7, and s the cycle for producing .having been moved from thestarting position to the opposite extreme position. An

' the operati starting band may be substituted therefor.

, This ap lication-is a division of my apo on,as long as the lamp 7operates. v

The function of the supplementary windings 14 and the positiveelectrodes is to supply an additional electro-motive-force during thealternation within which the critical or starting strain is applied. Itis evident that during this first alternation, the current must reachits maximum value after starting from.zero, whereas, when once the lampis operating normally, this maximum .current must be reached in onealternation,

starting, not from zero, but from the minimum value reached during theoperation which must at least be the minimum operatso ing current of thelamp. Once the lamp has/ reached a normal running condition, thesupplementary voltage supplied by the windings 14, 14 is no longerrequired and in fact will cause a waste of energy and disturbance of theoperation of the lampandshould be removed from further operation.

Theconductors 9 and 10 arejoined to thewindings of the auto-transformer21 through resistances l8, 18, provided with movable arms 19, 19. Thestarting band is .con ected by a wire 26 with the conductor 9, w ile ashunt circuit 27 containing a quick break switch 16 and a resistance 17is con nected between the conductors 9 and 8.

The switch arm 19 atthe left is represented at starting position, whilethe corresponding arm at the right is' represented as extra winding 14isadded at both ends of the winding 21, and each is connected throughone vor the other of the adjustable resistances to a separate positiveelectrode in the. lamp. \Vith the switches in the starting position, thesupply circuit 13,- 13 is closed and the snap or quick-break switch 16is operated. -By the action of the switch 16' and' the resistance 17 andthe coil 7 a high potential impulse is created at the starting band andthis is reinforced by the energy developed 'm the windings 14, 14. j Thelamp having been once' started into operation in this way, the switches19 aremoved from the starting position to the op crating position (thelatter being illustrated, as already ex lained, by the switch at theright" hand si e of thefigure) and on. continues with the windings 14 14disused. 1'20 ,t is' known that the critical strain may be applied totheapparatus through other instrumentalities than the starting band,-

and' if desired anyv means equivalent to the plication rial Number161,282, filed June 13th, 1903, and a companionto m'y'ap'plicationSerial Number 169,091, filed Au a 951,085; and a companion of myapplication Serial Number 540,738 filed January I claim as my invention:

1. In a system of electrical distribution, the combination with asupply, a mercury vapor apparatus comprising a highly exhaustedcontainer and suitable electrodes therefor, includinga plurality ofanodes, of means for supplying current alternately through two anodes,means for separately changing the supply voltages applied to the twoanodes, and energy storing means for steadying the total flow ofcurrent.

2. In a system of electrical distribution, the combination with asupply, a mercury vapor apparatus comprising a highly exhaustedcontainer and suitable electrodes therefor, including a plurality ofanodes, of means for supplying symmetrical relatively high voltage upontwo anodes and means for applying symmetrical relatively lower supplyvoltages upon the two anodes and discontinuing the supply from saidhigher voltage.

3. In a system of electrical distribution, the'combination with arectifier comprising an exhausted container, anodes and a cathodetherein, of an exciting winding supplied from a single phase source ofalternating current and connected to said cathode at an intermediatepoint, and means for independently connectingeach of the anodes at willdirectly to any one of a number of points of different potential in saidexciting winding.

Signed at New York in the county of New York and State of New York thisth day of May A. D. 1911.

PERCY l-I. THOMAS.

Witnesses:

WM. H. CAPEL, THos. H. BROWN.

